Great Barrier Reef could be dead by 2100: study

RISING sea temperatures could kill off the Great Barrier Reef by the end of the century, a scientist claims in a new book.

The coral would have to move 4000km southwards over 100 years to survive scientists’ worst-case scenario of a 4C degree rise in sea temperatures by 2100, Professor Ove Hoegh-Guldberg says.

In his book, Four Degrees of Global Warming: Australia in a hot world, the University of Queensland reef specialist says the outlook for the reef is bleak.

“In a four-degree world, the Great Barrier Reef will be great no longer. It would bear little resemblance to the reef we know today,” he wrote.

“There is little evidence that marine resources like the Great Barrier Reef possess the resilience to withstand the impacts of a dramatically warming world.”

Even a more conservative 2C temperature rise estimate would likely be too much for the reef to handle, he wrote.

The death of the almost 2300km-long reef would destroy its $6 billion tourism industry as well as other areas like fishing.

The book looks at how Australia will adapt to a warmer and drier climate in the next 100 years.

Warmer and more acidic seawater is a knock-on effect of increased atmospheric carbon levels.

Prof Hoegh-Guldberg wrote that sea temperatures rose by 0.5C in the 20th century but the effect is expected to speed up this century.

The result is that coral cannot move fast enough to cooler southern seas or genetically adapt fast enough to stay where they are.

“Unless we dramatically reduce carbon dioxide emissions which are acidifying our oceans and leading to their warming, we will face the destruction of the Great Barrier Reef and serious decline in our marine resources,” he wrote.